This year’s last Conversations on the Green will focus on truth and reason and feature Gen. Michael Hayden, former head of the CIA and National Security Agency.

“Truth Decay - National Security In The Age Of Lies” will be held at 3 p.m. on Sunday at St. John’s Parish Hall in Washington.

It will discuss the “threats facing the sprawling intelligence community and how the country is endangered by the growing tendency to see facts as malleable,” according to the event’s press release. Joseph Cirincione, president of The Ploughshare Fund, a global security foundation and leading civilian expert on nuclear arms will also be there.